System and method for managing construction machinery

ABSTRACT

Construction machine management, permitting operation of a construction machine only under specified conditions and inhibiting its operation in case it is in a state incongruent with preset working conditions. Working conditions for each construction machine are set up by a working conditions setup means, including a geographically divided working area and a working time zone in which a construction machine is allowed to operate in a specified working area. Setup working conditions are stored in a memory means. At the time of starting a construction machine, the status of the construction machine is checked for by a status checkup means which is adapted to check for current position of the construction machine and current time against the working area and working time zone of the setup working conditions. In case a construction machine is found to be in a state incongruent with both of the working area and the working time zone of the preset working conditions, the management inhibits operation of that construction machine.

TECHNICAL FIELD

[0001] This invention relates to a construction machine managementsystem and method for controlling operations of construction machinessuch as hydraulic power shovels or the like, and more particularly to aconstruction machine management system and method by which workingconditions such as geographical working area and working time zone canbe set up each construction machine under management surveillance.

TECHNICAL BACKGROUND

[0002] For prevention and early detection of construction machine theftswhich lately take place at an increasing frequency particularly forconstruction machines such as hydraulic power shovels, hydraulic cranes,bulldozer and the like, there has been proposed to establish aconstruction machine management center for surveillance of locations ofconstruction machines, for example, as in Japanese Laid-Open PatentApplication 2000-73411. According to this prior art, the position of aconstruction machine on a working site is measured on the basis of GPS(Global Positioning System) signals, using the resulting position datafor judging possibilities of a machine theft. Namely, in this case, aplace or an area where a construction machine is normally supposed to belocated is set up as a proper working area in a management server of theconstruction machine management center. Position data of variousconstruction machines under management are periodically reported to themanagement server. In case a construction machine is found to be locatedoutside a proper working area, it is presumed that a theft has occurredto that machine and a command signal is dispatched from the managementside for cutting off power supply to an engine starter motor, stoppingthe engine of the machine by cutting off fuel supply or taking othersuitable measures to prevent construction machine thefts.

[0003] By the way, at a working site, except for special cases, normallya construction machine is not put in operation 24 hours a day. Namely,it is usually the case that a construction machine is operated only in alimited time zone of a day and put at rest at night. Throughout the resttime zone at night, a construction machine is stopped on a predeterminedplace with or without a night guard. Even if a night guard is stationed,it is difficult to keep a machine constantly under strict surveillance.Maybe most of construction machine thefts can be prevented by increasingthe number of guards, but from the standpoint of personnel costs it isimpractical to increase the number of guards to a sufficient degree.

[0004] Constant surveillance of construction machines at respectiveworking sites, including rest periods at night, can be an effectivemeasure for preventing machine thefts or for quickly finding machinethefts. However, since data of locations of respective constructionmachines have to be acquired via communication satellites, constantlyconnected surveillance will require vast communication costs. Inaddition, there will arise another problem that batteries on therespective construction machines are consumed markedly because have tobe constantly kept on. Therefore, in a rest period, it is the usualpractice to acquire data of construction machine locations at timeintervals of one to several hours. If a construction machine theft takesplace immediately after acquisition of location data, detection of themachine theft can be delayed for several hours to make it difficult toget the machine back in an early stage.

[0005] Normally, a transportation means such as trailer or the like isused for transporting a construction machine like a hydraulic powershovel from one place to another, and the automotive base carrier of theconstruction machine is put in travel at the time of getting machineonto a transportation means. Similarly, the machine engine has to bestarted to move the construction machine in the case of a machine theftas well.

DISCLOSURE OF THE INVENTION

[0006] In view of the foregoing situations, it is an object of thepresent invention to provide construction machine management system andmethod which permits operations of a construction machine only underspecified working conditions including conditions of a working time zonein addition to geographic regional conditions to prevent constructionmachine thefts from happening or to spot and find a stolen constructionmachine very quickly in case of a machine theft.

[0007] According to the present invention, in order to achieve theabove-stated objective, there is provided a construction machinemanagement system, managing construction machines in such a way as topermit operations of construction machines only under specified workingconditions while inhibiting operations of the construction machines whennot in agreement with the specified working conditions, the systemcomprising: working condition setup means adapted to set up workingconditions for each one of the construction machines, the workingconditions including a working time zone in addition to a working areawith geographical bounds; a memory means for storing the workingconditions set up by the working condition setup means; a status checkupmeans adapted to check for current status of the construction machinesagainst the working area and working time zone of the setup workingconditions; and an operation inhibiting means adapted to inhibitoperation of the construction machines when in a state incongruent withthe setup working conditions with regard to both of the working area andworking time zone.

[0008] As working conditions of a construction machine, two differentkinds of working conditions, a geographical working area and a workingtime zone in that working time area, are set up beforehand. The workingarea is a regional area which contains a working site, and its boundsare defined depending upon the nature of a working site, the nature ofoperations to be performed, the type of the construction machine, anautomotive traveling type or a fixed type, and the maximum distance overwhich the construction machine will be moved during operation. At thetime of setting up the working area, it may be defined by latitudes andlongitudes or alternatively it may be selected by way of anadministrative division such as a state, prefecture, county, city,village or an urban or suburban district.

[0009] The working time zone is set up on the basis working hours at aworking site, and the management is not necessarily limited to anexpected working time zone of a construction machine. Namely, even whenthe construction machine is not in operation or is at rest, there islittle possibility of machine thefts if other construction machines arein operation nearby or if some workers are still at work on the sameworking site. On the contrary, even in a time zone outside an expectedworking time zone of a construction machine, there may arise a necessityfor putting the machine in operation in connection with a work oractivity which is still going on at the same working site. Therefore,exclusion of such machine operations in a safe time zone might give riseto inconvenient situations. For example, a working time zone can be setup on the basis of work starting and ending times at a working sitewhere a construction machine is located, adding an extra allowance timemargin of a certain length before and after the work starting and endingtime points. Thus, various situations at a working site should be takeninto consideration at the time of determining the work starting andending times for the setup of the working time zone. Depending upon thenature of the work, the working time zone may be extended to 24 hours aday.

[0010] In setting up the above-mentioned working conditions, one set ofworking conditions including one working area and a working time zone inthat working area can be set up separately machine by machine, orworking conditions involving a plural number of working areas and aworking time zone in each one of the working areas can be set upcollectively. In the latter case, it becomes unnecessary to set up newworking conditions even in case where one construction machine isrelocated from one working site to another. In addition, it becomespossible to set up same working conditions for a plural number ofconstruction machines, permitting to complete setup operations in afacilitated and time-saving manner. Accordingly, in a case where a setupformat is arranged to permit setup of a plural number of working areasalong with working time zones in the respective working areas, it ispossible to set up the same working conditions for a plural number ofconstruction machines which are located at different working sitescollectively in a very time-saving manner.

[0011] In a case where a large number of construction machines are putunder management and surveillance of a construction machine managementcenter, a management device such as a management server is set up at themanagement center. In some cases, communication terminals such aspersonal computers, which are owned by clients of construction machinemanagement service or by authorized persons who have interests in aconstruction machine or machines under management, are connected themanagement center through a network. According to the present invention,preferably the management system is basically configured to include aworking conditions setup means, a memory means for storing setup workingconditions, a status checkup means, and an operation inhibiting means.In case a number of authorized communication terminals are connected tothe management server, the working conditions setup means can beprovided on the side of the communication terminals. Further, theworking conditions setup means can be provided on the side ofconstruction machines although in this case it is necessary to providemeasures for preventing alteration of conditions by a thief.

[0012] The working condition memory means and the status checkup meansare provided either on the side of a construction machine or on the sideof the management center. Since the operation inhibiting means isprovided on the side of a construction machine, an operation inhibitingsignal can be dispatched thereto more directly if the memory means andthe status checkup means are provided also on the side of theconstruction machine. In case these means are provided on the side ofthe management center, it becomes necessary to use communication meansto transmit an operation inhibiting means to the construction machine.The operation inhibiting means serves to produce and dispatch a commandsignal for inhibiting operation of the construction machine. In thisregard, it is the most direct action to inhibit engine operation uponreceipt of an operation inhibiting signal. For inhibiting engineoperation, it is the general practice to prevent an engine from gettingstarted despite a engine start-up operation. In case the engine isalready in operation, a countermeasure may be taken to stop the engine.Furthermore, in case the construction machine is a hydraulic type, themanagement system may be arranged to stop operation of a hydraulicactuator which is provided on the construction machine to performvarious operations.

[0013] As communication means for exchanging data between the managementcenter and each one of the construction machines under the managementsurveillance, it is desirable to utilize a communication satelliteconsidering that in many cases construction machines are used in remotesecluded places in an inferior communication environment. However, it ispossible to use other communication means, for example, ground wavecommunication means, mobile phone communications or the like. The dataof current position of a construction machine can be acquired from theGPS satellites mentioned hereinbefore.

[0014] Therefore, according to the present invention, operation of aconstruction machine is permitted only under preset specific workingconditions, and inhibited in case the status of the construction machineis found to be incongruent with the preset working conditions. Theworking conditions, including a geographic working area where aconstruction machine is supposed to be for operation and a working timezone in that working area, are set up for each construction machine.Every time when a construction machine is started, the status of themachine is checked against the setup working conditions to see whetheror not the machine is in a state congruent with setup workingconditions. In case both of the working area and working time zone ofthe setup working conditions are not satisfied, a suitable measure istaken to inhibit start-up or operation of the construction machine.

[0015] As another method of construction machine management, forpermitting operation of a construction machine only under presetspecific conditions and otherwise inhibiting start-up or operation ofthe construction machine, it is possible to set up a plural number ofworking areas and working time zones in the respective working areaswith regard to one construction machine. In this case, every time theconstruction machine is started, the status of the machine is checkedagainst the setup working conditions on the basis of current positionand present or current time to check whether or not it is in a statecongruent with the preset working conditions. Start-up operation of theconstruction machine is allowed only when the machine is located in oneof the setup working areas and in a working time zone which has been setup for that particular working zone.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In the accompanying drawings:

[0017]FIG. 1 is a schematic illustration of a construction machinemanagement system according to one embodiment of the present invention;

[0018]FIG. 2 is a diagram of a circuitry including a constructionmachine controller and a management server;

[0019]FIG. 3 is a diagrammatic illustration showing a first setup formatfor setting up working conditions of a construction machine;

[0020]FIG. 4 is a flowchart of a checkup operation to be executed forchecking up the current status of a construction machine on the basis ofworking conditions set up by the first setup format of FIG. 3;

[0021]FIG. 5 is diagrammatic illustration showing a second or anothersetup format for setting up working conditions of a constructionmachine; and

[0022]FIG. 6 is a flowchart of a checkup operation to be executed forchecking up working conditions of construction machines on the basis ofworking conditions set up by the use of the second setup format.

BEST MODE FOR CARRYING OUT THE INVENTION

[0023] Hereafter, the present invention is described more particularlyby way of its preferred embodiments with reference to the accompanyingdrawings. Firstly, shown in FIG. 1 is the general configuration of aconstruction machine management system as a whole. By way of example,the management system in the following description is arranged to managea plural number of construction machines by a management server at aconstruction machine management center, and a plural number ofauthorized communication terminals (e.g., personal computers) areconnected to the management server. In this instance, the term“authorized communication terminals” means communication terminals whichare authorized of access to the management server by the managementcenter, including, for example, communication terminals installed atvarious branch offices of one and same business entity which solely orjointly owns the management server, or communication terminals owned bya plural number of construction machine rental contractors which arejointly put under the surveillance service of the management center.

[0024] Referring first to FIG. 1, indicated at 1 is a management center,established for management of construction machines 2. A managementserver 3 is installed at the management center 1, and a plural number ofcommunication terminal devices 4 are connected to the management server3, for example, through the Internet network 5. The communicationterminal devices 4 are provided for use by the users of the constructionmachines or other persons who have interests in the constructionmachines, in acquiring data of current status of the respectiveconstruction machines. Denoted at 6 is a working site where aconstruction machine 2 is located for operation. The constructionmachine 2 is equipped with a GPS antenna 7 and a data communicationdevice 8. The GPS antenna 7 is provided on each construction machine forthe purpose of getting its own position data from satellites 9. Further,data are exchanged between the data communication device 8 on the sideof the construction machine 2 and a data communication device 10 whichis provided on the side of the management server 3. In this instance,the communications between the management server 3 and the communicationdevice 8 of the construction machine 2 are communications of bothdirections utilizing mobile phone ground waves or a wirelesscommunication satellite.

[0025] In the following description, among various construction machinemanagement services which can be provided by the management center 1 inconnection with machine operations, machine troubles and accidents, thepresent invention is described as applied to construction machine theftmanagement. In principles, the machine theft management operates on asystem which is arranged to periodically check up the current status ofeach construction machine, stolen or not stolen, presuming that themachine has been stolen by a theft and sending a command signal toinhibit operation of the machine, for example, to inhibit engine startof the machine in case the machine is found to have been removed from aproper working area without any legitimate procedure. Arrangements canbe made to stop operation of a hydraulic actuator in case the stolenmachine is a hydraulic drive type. An inhibiting countermeasure is takenby applying a control signal to a corresponding operating part from thecontroller 11 of the construction machine 2.

[0026] Accordingly, for machine theft management, it is necessary toacquire data of current locations of the respective constructionmachines 2, namely, current position data of the construction machines2. Position data of this sort can be obtained by measurements based onGPS signals. The method of measuring positions on the basis of GPSsignals is well known in the art, so that detailed explanation in thisregard is omitted here.

[0027] Let alone a construction machine 2 of the type which is fixedlyset up at a certain position on a working site 6, an automotive typeconstruction machine 2 which is moved on and across a working site 6should be regarded as being at a proper location as long as it is in aspecified working site 6 or in areas around or immediately bordering onthat working site 6, and regarded as having been stolen only when it isabsent in the specified working site 6 or bordering areas. Therefore, aproper working area in which an automotive construction machine 2normally can move around is set up for each working site 6 beforehand.Namely, a proper working area is set up for each construction machine 2beforehand, and a machine theft is suspected when the machine is movedout of the proper working area without a permission.

[0028] By the way, normally construction machines 2 are not put inoperation 24 hours a day. Namely, in most cases the constructionmachines 2 are put at rest at night except civil road construction orrepair works which are carried out nighttime, rather avoiding a daytimeperiod when traffic is dense. Further, it is often the case that thesame work is started and ended at different times in different regionsand in different seasons. There is little possibility of a constructionmachine 2 in a working time zone when at least a worker is at work atthe working site 6. A construction machine theft is most likely to occurin a rest period at night when no one is at the working site 6. As faras a rest period is concerned, there will arise no problems inparticular even if operation of a construction machine 2 is totallyinhibited. Therefore, a working time zone is set up for eachconstruction machine 2 in relation with its working site and the natureof its work, permitting operation of the machine 2 in a preset workingtime zone and inhibiting operation at a time point outside the presetworking time zone, that is to say, inhibiting operation during a restperiod.

[0029] In order to carry out machine theft management, it is necessaryto provide working conditions setup means, memory means, status checkupmeans and operation inhibiting means. The working conditions setup meansis necessary for setting up working areas and working time zones of theconstruction machines 2. The memory means is for storing data of theworking areas and working time zones set up by the working conditionssetup means. The status checkup means functions to check the status of aconstruction machine, as to whether or not a construction is currentlyin a preset working area and as to whether or not the constructionmachine is in a preset working time zone for that working area. In caseit is judged by the status checkup means that operation of theconstruction machine should be inhibited, a command signal is dispatchedto inhibit an engine start-up or to stop the engine of the machine.

[0030] Therefore, as shown in FIG. 2, the working conditions setup meansis provided on the side of the management server 3. The managementserver 3 is provided with an input means 12 including a keyboard and amouse. These input means 12 are used at the time of setting up workingconditions. Alternatively, working conditions can be set up from thecommunication terminal device 4 via the Internet network 5. In thelatter case, the communication terminal device 4 constitutes the workingconditions setup means. Further, in a case where an input means like apersonal computer is connectible to the controller 11 on the side of aconstruction machine 2, it also can function as a working conditionsetup means.

[0031] The memory means which stores data of setup working conditions isclosely related with the status checkup means. In a case where a statuscheckup operation is carried out on the side of the management server 3,arrangements are made to set up working conditions in the managementserver 3. In the particular embodiment shown, the controller 11 isarranged to carry out status checkups and therefore the memory means 13is provided in the controller 11. In this instance, the memory means 13is constituted by a working conditions storage portion 13 a and aworking time zone storage portion 13 b. Since the working conditionssetup means is provided on the side of the management server 3, data ofsetup working conditions are transmitted to the data communicationdevice 10 of the construction machine 2 through the data communicationdevice 8 of the management server 3. A communication control circuit 16is provided in the controller 11, and, by this communication controlcircuit 16, data of setup working area and data of setup working timezone which have been received from the management server 3 are allocatedto the working area storage portion 13 a and the working time zonestorage portion 13 b of the memory means 13, respectively.

[0032] The controller 11 is provided with a status checkup circuit 15 asthe above-mentioned status checkup means. This status checkup circuit 15is arranged to make judgements as to whether or not a constructionmachine 2 is located within a preset working area and, make judgementsas to whether or not the current status of the construction machine 2 isin agreement with present working conditions when the constructionmachine 2 is about to be started. In order to carry out status checkupoperations, the controller 11 is provided with a position dataprocessing circuit 14 thereby to measure the current position of theconstruction machine 2 on the basis of GPS signals received from thesatellites 9 through the GPS antenna 7, and a clock circuit 17. In thisinstance, a status checkup operation is carried out basically regularlyat predetermined time intervals (regular status checkup operations).Therefore, even when the construction machine 2 is in a rest period,power supply of the controller 11 is turned on at predetermined timeintervals by the clock circuit 17 to execute a regular status checkup.Regular status checkup operations alone may be sufficient in some cases.However, in addition to the above-described regular status checkups, itis desirable to make a status check every time when an attempt is madeto start the construction machine 2 (a start-up status checkupoperation), because a machine is started to get it onto a trailer orother transportation means in most cases of machine thefts. In thisconnection, the controller 11 is provided with a power supply controlcircuit 18 which functions to turn on power supply every time ondetection of an engine start key signal. Accordingly, an on-start statuscheck is executed every time when a power-on signal is applied to thepower supply control circuit 18. Further, the controller 11 is providedwith a engine condition checkup circuit 19 to which a power generationsignal of an alternator 25 is applied for the purpose of making ajudgement as to whether or not the construction machine 2 is currentlyin operation.

[0033] In case the construction machine 2 is found to be located in apreset proper working area and in a preset working time zone as a resultof the status checkup operation by the status checkup circuit 15, thestatus checkup operation is completed without taking anycountermeasures. If the construction machine 2 is judged as beinglocated outside a proper working area or outside a preset working timezone by the status checkup operation, an inhibiting signal is dispatchedfrom an operation inhibition signal output circuit 20 thereby to lockthe operation of an engine starter motor 20 or to stop the engine of themachine 2. As a consequence, in case the construction machine 2 isjudged as being actually moved, it is compulsorily brought to a stop. Incase the status of the construction machine 2 is judged as being in theprocess of staring the engine, an inhibiting signal is dispatched tocancel all of following starting operations. In order to spot a machinetheft in an early stage and to take quickly a countermeasure to themachine theft, it is desirable to make arrangements to send a reportquickly to the management server in case the construction machine 2 isjudge as being located outside a proper preset working area, being putin operation or being started outside a preset working time zone.

[0034] ROM 22 in the controller 11 contains all necessary instructionsand procedural steps of the above-described status checkup operations.On starting a status checkup operation, data concerning the procedure ofthe checkup operation are read out from ROM 22 and put in RAM 23.Necessary data which come out as a result of a status checkup operationare also stored in RAM 23. Respective parts of the controller 11 areoperated under control of CPU 23.

[0035] For management of construction machines 2, it is necessary in thefirst place to set up a working area and a working time zone for eachconstruction machine 2. These working conditions are set up by themanagement server 3. For example, as shown in FIG. 3, a workingcondition setup format is put on a display screen 3 a of the managementserver 3, including a “MACHINE ID INPUT” box R1, a “WORKING PERIODINPUT” box R2, a “WORKING TIME ZONE INPUT” box R3 and a “MAP” box M tobe used in setting up a working area. More particularly, by the use ofthe input means 12 such as keyboard and mouse of the management server3, the type and ID number of the construction machine to be put undermanagement surveillance are entered in the “MACHINE ID INPUT” box R1,followed by entering of a working period in the “WORKING PERIOD INPUT”box R2.

[0036] Next comes the setup of a working area of the constructionmachines 2. In the particular embodiment shown, arrangements are made toselect a working area by way of a relatively large unit ofadministrative division such as a state, prefecture county or the like.In this instance, a working area is selected by clicking a correspondingpart of the map M. If necessary, the working conditions setup format maybe arranged in such a way as to permit selection of a working area or aplural number of working areas by way of a smaller administrativedivision unit or units such as a city, a village and an urban, suburbanor rural district. In this connection, it is also possible to set up aworking area which is defined by latitudes and longitudes. Then, aworking time zone of the construction machine 2 is set up by the“WORKING TIME ZONE SETUP” box R3. Namely, for setting a working timezone, a starting time and an ending time are entered in the “WORKINGTIME ZONE SETUP” box R3.

[0037] The above-described working conditions of the constructionmachine 2 can be set up before taking the machine out of a garage. Ifdesired, setup and alteration of working conditions of a machine can bemade even after delivery to a working site 6. In relation with setupworking conditions, respective construction machines are put undersurveillance by the management server 3. Data of setup workingconditions are transmitted to a corresponding construction machine 2 andstored in the working area storage portion 13 a and the working timezone storage portion 13 b of the memory means 13, respectively.

[0038] For each construction machine, a status checkup operation isexecuted regularly at predetermined time intervals to check if thecurrent status of the machine is in agreement with preset workingconditions, that is to say, to see if the construction machine is in anormal state which is congruent with preset working conditions or in anabnormal state which is incongruent with preset working condition, withpossibilities of a machine theft. In addition to the regular statuscheckups, a status checkup operation is also carried out as an on-startcheckup every time the construction machine is started. The procedure ofthe status checkup operation is explained below step by step withreference to the flowchart of FIG. 4.

[0039] On starting a status checkup operation, a start index FLAG is setat “0” (Step 1), and the current position of the construction machine 2is determined at the position data processing circuit 14 on the basis ofGPS data received from the satellites 9 (Step 2), writing data of thecurrent position of the construction machine 2 in RAM 23 (Step 3). Then,the current time is read out from the clock circuit 17 (Step 4),followed by writing of the current clock reading in RAM 23 (Step 5).

[0040] In the next place, data of the working area of the constructionmachine 2 are read out from the working area storage portion 13 a of thememory means 13 and compared with data of the current position of theconstruction machine 2 to check whether or not the construction machine2 is located in the preset proper working area (Step 6). If theconstruction machine 2 is judged as being located within the properworking area, the working time zone of the machine 2 is read out fromthe working time zone storage portion 13 b and compared with the currenttime or current clock reading to check whether or not the constructionmachine 2 is in the preset working time zone (Step 7). In case theconstruction machine 2 is judged as being in the preset working timezone, the checkup operation is completed at this point.

[0041] On the other hand, in case the construction machine 2 is judgedas being located outside the proper working area at Step 6, “1” is.substituted into FLAG (Step 8), and the operation proceeds to Step 9 togo to a next procedure. In case the construction machine is judged asbeing outside the preset working time zone in Step 7, the operation alsoproceeds to Step 9. At Step 9, a check is made as to whether or not theconstruction machine 2 is in the process of engine start outside thepreset working area or outside the preset working time zone, namely, acheck is made as to whether or not the engine key switch is turned on.If the engine key signal is on, the operation goes to the next Step 10to take a countermeasure which inhibits an engine start. Morespecifically, an inhibition signal is applied to a starter motor 20 fromthe operation inhibiting signal output circuit 21 thereby to lock theoperation of the starter motor 20. In case the engine key signal isturned out to be off at Step 9, the operation goes to Step 11 to checkwhether or not the engine is in operation. If the engine is turned outto be in operation at Step 11, the operation goes to Step 12 to take ameasure for stopping the engine.

[0042] In case the engine of the construction machine is judged as beingnot in operation at Step 11, the operation goes to Step 13 to checkwhether or not FLAG is “1”, that is to say, whether or not the currentposition of the construction machine 2 is outside the preset workingarea. In case FLAG is judged as being “1” at Step 13, or after taking acountermeasure to inhibit engine start at Step 10 or after taking acountermeasure to stop the engine at Step 12, data of the currentposition of the construction machine 2 and the current clock reading arereported to the management center through the data communication device8.

[0043] As described above, the status checkup operation checks for notonly whether or not the construction machine is located outside a presetworking area but also whether or not the construction machine is put inoperation outside a preset working time zone, inhibiting the operationof the machine as soon as machine is found to be in operation outsidethe preset working time zone even if it is located in the preset properworking zone. This sort of status check is extremely effective inpreventing machine thefts especially in rest periods at night when noone is stationed at a working site 6 and a machine theft takes place ata high frequency.

[0044] In setting up the above-described working conditions includingthe working area and the working time zone, it is possible to set upworking conditions of a plural number of construction machines on onesetup format. More particularly, a multiple setup format may be put onthe display screen 3 a of the management server 3 as shown in FIG. 5. Inthis case, the setup format is arranged to enter a plural number ofworking time zones in a “WORKING TIME ZONE SETUP” box R3 in combinationwith working areas selected on a map M. Accordingly, in a case where aregion A is selected and set up as a working area on the map M, aworking time zone in that working area A is entered at a first inputposition in the “WORKING TIME ZONE SETUP” box R3 to set up a workingcondition A. Next, a region B is selected and set up as a working areaon the map M, and a working time zone in the working area B is enteredin a second input position in the “WORKING TIME ZONE SETUP” box R3 toset up a second working condition B. Similarly, working condition C andworking condition D are successively set up on the same setup format. Inthis case, an N-number of working conditions can be set up collectivelyon one setup format, and data of an N-number of working area are storedin the memory means 13 along with data of respective working time zones.In this instance, it is possible to set up a plural number of workingconditions for one construction machine or to set up a plural number ofworking conditions for a plural number of construction machines. Forexample, it is possible to set up the same working conditions for all ofconstruction machines, by not specifying machine ID numbers of themachines on the setup format.

[0045] In case an N-number of working conditions have been set up in theorder of A, B, C, . . . N as described above, a status checkup operationis repeated for N-number of times and in that order. Accordingly, statuscheckup operations are carried out through the procedural steps as shownin the flowchart of FIG. 6.

[0046] Firstly, upon starting a status checkup operation, start indexFLAG1 and FLAG2 are set at “0” (Steps 20 & 21), and a checkup repetitionnumber n is set at 1 (Step 22). In the next place, the current positionof the construction machine 2 is determined on the basis of positiondata from GPS satellites (Step 23). Data of the determined currentposition of the construction machine 2 are written into RAM 23 (Step24). Current time is read out from the clock circuit (Step 25), and thedata of the current time reading are written into RAM 23 (Step 26).These steps 23 to 26 are same as Steps 2 to 5 in the flowchart of FIG.4.

[0047] After acquiring the current position and the current time, thecheckup repetition number n is compared with a preset number N (Step27). If n<N, (n) working area and (n) working time zone are read outfrom the memory means 13 (Step 28), checking whether or not the currentposition of the construction machine 2 is within the n-th working area(Step 29). In case the construction machine 2 is judged as being withinthe proper working area, the operation goes to a next step to checkwhether or not the current time is within the (n) working time zone(Step 30). In case the construction machine 2 is judged as being locatedwithin a proper working area and within a proper working time zone, “1”is substituted into FLAG1 and the operation goes to Step 33 no matterwhether the construction machine 2 is at rest or in operation. In casethe construction machine is judged as being located outside a presetworking area, the operation goes straight to Step 33. In case theconstruction machine 2 is not in a preset working time zone, “1” issubstituted into FLAG2 at Step 31 and the operation proceeds to Step 33.At Step 33 the state of FLAG1 is checked for, and, if FLAG1 is in thestate of “0”, 1 is added to n (Step 34) before repeating the checkupoperation on the next working condition. Namely, Steps 27 to 33 arerepeated to check whether or not the current position of theconstruction machine 2 and current time are within the limits of the(n+1) working conditions.

[0048] If FLAG1 is judged as being “1” at Step 33, the status checkupoperation is completed because the construction machine 2 is in a properstate in agreement with a plural number of preset working conditions.

[0049] On the other hand, if FLAG1 is still in the state of “0” evenafter repeating the status checkup operations for a preset number (N) oftimes, it means a failure in satisfying all of the preset workingconditions, namely, there is a possibility of machine theft. Therefore,if the engine key is found to be on, a countermeasure is taken toinhibit start of the engine (Steps 36 & 36). If the engine is inoperation, a countermeasure is taken to stop the engine (Steps 37 & 38).In case the starter key signal is off and the engine is at rest, FLAG2is checked for its value (Step 39). Namely, in case FLAG2 is “1”, thecheckup operation is ended, judging that the construction machine islocated within a preset proper working area past a preset working timezone and has not been moved out of the proper working area. On the otherhand, FLAG2 is still in the state of “0”, the machine 2 is judged asbeing not located in any of preset working areas possibly due to amachine theft. In this case, after taking a countermeasure to inhibitengine start or to stop the engine or as soon as FLAG2 is found to benot in the state of “1”, the current position of the constructionmachine 2 is transmitted to the management server3 at the managementcenter 1 to complete the status checkup operation.

POSSIBILITY OF INDUSTRIAL UTILIZATION

[0050] According to the present invention with the arrangements asdescribed above, each one of construction machines are checked againstpreset working conditions which include working time conditions inaddition to geographical areal conditions as checkup criteria,permitting to spot the location of a construction machine promptly incase of a machine theft or the like.

What is claimed is:
 1. A construction machine management system, formanaging construction machines in such a way as to permit operations ofconstruction machines only under specified working conditions whileinhibiting operations of said construction machines when not inagreement with said specified working conditions, said systemcomprising: working condition setup means adapted to set up workingconditions for each one of said construction machines, said workingconditions including a working time zone in addition to a geographicallydivided working area; a memory means for storing the working conditionsset up by said working condition setup means; a status checkup meansadapted to check for current status of said construction machinesagainst said working area and working time zone of said setup workingconditions; and an operation inhibiting means adapted to inhibitoperation of said construction machines when in a state incongruent withsaid setup working conditions with regard to both of said working areaand working time zone.
 2. A construction machine management system asdefined in claim 1, wherein said working conditions setup means isadapted to set up said working area on the basis of latitudes andlongitudes or on the basis of known geographical divisions, and saidstatus checkup means is adapted to measure current position of aconstruction machine on the basis of position data acquired from GPSsatellites.
 3. A construction machine management system as defined inclaim 1, wherein said working conditions setup means is provided on theside of a management device holding all of construction machines undersurveillance and adapted to exchange data with respective constructionmachines through wireless communication means.
 4. A construction machinemanagement system as defined in claim 3, wherein said working conditionssetup means is provided in a communication terminal connected to saidmanagement device through a communication network.
 5. A constructionmachine management system as defined in claim 1, wherein said memorymeans and said status checkup means are provided on the side ofconstruction machines.
 6. A construction machine management system asdefined in claim 1, wherein said working conditions setup means isarranged into a format permitting a plural number of working conditionsfor one construction machine, along with working time zones inrespective setup working areas.
 7. A construction machine managementsystem as defined in claim 1, wherein said operation inhibiting means isadapted to inhibit operation of an engine or a hydraulic actuator of aconstruction machine.
 8. A method of managing construction machines insuch a way as to permit operations of construction machines only underspecified working conditions while inhibiting operations of saidconstruction machines when not in agreement with said specified workingconditions, said method comprising the steps of: setting up workingconditions for a construction machine, including a geographicallydivided working area and a working time zone for operation in saidworking area; checking for current location of said construction machineand current time against setup working area and working time zone everytime which said construction machine is started, to check whether or notstatus of said construction machine is in agreement with said workingconditions; and inhibiting operation of said construction machine whenincongruent with either said working area or working time zone of saidworking conditions.
 9. A method of managing construction machines insuch a way as to permit operations of construction machines only underspecified working conditions while inhibiting operations of saidconstruction machines when not in agreement with said specified workingconditions, said method comprising the steps of: setting up for aconstruction machine working conditions including a plural number ofgeographically divided working areas and a working time zone foroperation in each working area; checking for current location of saidconstruction machine and current time against the setup working area andworking time zone every time when said construction machine is started,to check whether or not status of said construction machine is inagreement with said working conditions; and permitting start-up of saidconstruction machine only when said construction machine is located inone of the setup working areas and within a working time zone for thatparticular working area.